1. Field of the Invention
The invention relates to a printing apparatus, more particularly, to a three-dimensional printing apparatus.
2. Description of Related Art
Rapid Prototyping (RP) is a new prototype manufacturing technology developed in the mid-80s. Rapid Prototyping has combined technologies such as mechanical engineering, Computer-aided design (CAD), digital control technology, laser technology and material science, allowing the design concept to be automatically, directly, quickly and accurately transformed into a prototype with certain functionalities or manufacturing parts, as a result, assessment, modification and functionalities test to the design concept can be quickly performed, thereby remarkably reducing the developing and manufacturing process of the product. With advantages like agility, adaptable for all sorts of forms, high flexibility and high integration, it is widely applied in different technical fields such as mechanical, motor vehicle, electronic, communication and aerospace technology. During an initial stage of the development, a CAD file of required drawings is designed, an original model is manufactured before the actual production, and used for design confirmation, product modification, functionality test and molding process, such model is known as the prototype.
Different prototyping materials are used according to different prototyping technologies, in which their prototyping principle and system features are also different from each other. For example, stereo lithography apparatus (SLA) is the first commercialized system with biggest share of market. The processing principle thereof is consisted of the following steps: scanning the liquid photosensitive polymer by using HeCd laser or Argon laser; thereby generating a polymerized cured thin-film; next, bringing the lifting table down and then up again; applying another layer of polymer resin on the surface of the desired processing area; scraping off the liquid surface with a scraper until the surface is horizontal; scanning the surface with laser so the processing area is closely combined with the upper layer thereof; repeating above steps until the desired three-dimensional work piece is generated. In addition, the image-forming system using SLA technology is either the laser scanning system or the light projector, since the hardware of the system is complex and large in size, and the image-forming distance for the laser scanning system or the projector needs to be included in the machine, the overall size of the such system cannot be miniaturized.
Regarding related art of the prototyping technology, U.S. Pat. No. 5,980,813 has disclosed a rapid prototyping method using multilayer materials. US Patent Publication No. 20100262272 has also disclosed an apparatus of manufacturing three-dimensional object by using curable materials.